All, I am an engineer that occasionally needs to modify or rework circuit boards. I have a hot air rework station that uses a diaphragm pump to push air through a heating element. The result is air up to 550 degrees celcius. I can effectively rework most circuit boards. Unfortunately the pump is so load it makes the unit unusable. The air nozzle has a fairly short hose. The noise is generated by the vibration of the diaphragm air pump. example of a similar hot air rework station: http://www.kerrywong.com/2011/12/07/x-tronic-4040-hot-air-reworksoldering-station-ii/ The pump has two diaphragms that are moved by a shaft that is connected to both. The shaft is moved by two AC coils out of phase. I have tried several methods of damping the vibration to reduce the noise without luck. I'm thinking about securing some springs to case of the unit. I'd probably frame up the unit with additional bracing and secure the pump with the springs. Since the pump is likely vibrating at 60Hz and generating high frequency vibration, I believe a smaller spring is the right choice. Is there someone that can validate that?